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**sandra****Guest**

i need some help on the following question......

The probability that a glass fiber will shatter during an experiment is believed to follow a poisson distribution. In certain apparatus, it was found that, on average, 7 glass fibers shattered. Determine the probability that, during a single demonstartion of the experiment,

i) two glass fibres will shatter

ii) at most two glass fibres will shatter

im finding it really difficult.

Thank you

**ryos****Member**- Registered: 2005-08-04
- Posts: 394

Poisson? Isn't that french for "fish"?

Sorry, I don't have anything helpful to say.

El que pega primero pega dos veces.

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**kempos****Member**- Registered: 2006-01-07
- Posts: 77

1. P = (e^(-7)* 7^2)/2! = 0.02234121335

where 7 is expeted number of occurences and two the number of occurences we want to get.

2. P(0) + P(1) + P(2)

But I'm really not sure. Hope some guys here will be able to help you with this problem.

*Last edited by kempos (2006-01-18 16:48:32)*

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